Ghana's goalkeeper Eric Antwi. (Photo: AP)
France will take on either Iraq or Uruguay, who played their semifinal later Wednesday.
Two minutes before halftime, Thauvin was set up by Jean Christophe Bahebeck, dribbled past Ghana goalkeeper Eric Antwi and netted into the empty goal.
Ebenezer Assifuah equalized for Ghana in the 47th with his fifth goal of the tournament as he collected the ball with his back to the goal, held off three France defenders before directing a 20-meter strike past goalkeeper Alphonse Areola.
Thauvin found the net again coming in from the right and beating Antwi with a low shot at the near post in the 74th.
France defender Samuel Umtiti was sent off for receiving a second booking in the 80th and will miss the final.
France, improving on its best result of fourth two years ago, can become the first European winner since Spain in 1999, which has been the sole European victory in the competition for the past 20 years.
France, which had beaten Ghana 3-1 in the group stage two weeks ago, started the semifinal full of confidence following convincing wins in the knockout stage against Turkey (4-1) and Uzbekistan (4-0).
Ghana missed suspended key defenders Joseph Attamah and Lawrence Lartey as well as midfielder Moses Odjer, who scored the first goal in the 4-3 quarterfinal defeat of Chile.
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